Floating point precision with writeln

[Serg Gini]

On Saturday, 1 June 2024 at 10:44:50 UTC, Maynard Kaiser wrote:
> Top o' the day, folks!
>
> I'm working with floats, doubles to be precise. Whenever I 
> write them to the console, the maximum precision I get is 5 
> digits after after the separator.
> If I wanted to have 8 or 9 digits after the separator, what 
> would I have to do?

```d
import std;
void main()
{
     writefln("%1.14f", std.math.PI);
}
```